diff --git a/.gitignore b/.gitignore
index cff8e53..fc099d0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,2 @@
 /zsync-0.6.2.tar.bz2
 /zsync-0.6.3.tar.bz2
-/zsync-0.6.4.tar.bz2
-/zsync-0.6.5.tar.bz2
diff --git a/sources b/sources
index 7391c8d..bbf2246 100644
--- a/sources
+++ b/sources
@@ -1 +1 @@
-SHA512 (zsync-0.6.5.tar.bz2) = c70dab9a9190933e9318d3e5b377c4f32be26fe81dedaec5448dd54d570c42918425d87f6763edc1585a741b3bb8e7a2d30714a99bd54164959e011ce4ab5345
+SHA512 (zsync-0.6.3.tar.bz2) = b7b9f16c9dc9d3d7753eb43e57d8c4bc8adea37ed3b6372829b466d3b010dd2c287a1de2ec02a5f1a4d96ee52fdcfec6d6021776368fe4a3af862c785de20089
diff --git a/zsync-0.6.3-fix-tests.patch b/zsync-0.6.3-fix-tests.patch
new file mode 100644
index 0000000..4134b10
--- /dev/null
+++ b/zsync-0.6.3-fix-tests.patch
@@ -0,0 +1,21 @@
+From a5cb28f923dd3cfdeb65e2930dd1faa727c2abf8 Mon Sep 17 00:00:00 2001
+From: Colin Phipps <cph@moria.org.uk>
+Date: Thu, 29 May 2025 08:33:11 +0100
+Subject: [PATCH] Update check-zsyncmake for changes in 208ef06.
+
+---
+ c/check-zsyncmake | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/c/check-zsyncmake b/c/check-zsyncmake
+index 3006230..08791e1 100755
+--- a/check-zsyncmake
++++ b/check-zsyncmake
+@@ -4,6 +4,6 @@ ${top_builddir-.}/zsyncmake -u foo -f foo ${srcdir-.}/INSTALL
+ 
+ # Note TAB required for Solaris cksum
+ x=`perl -pe 's/^(zsync:).*$/$1 XXX/; s/^(MTime:)(.*)$/my ($x, $y) = ($1, $2); $y =~ s![a-zA-Z0-9]!_!g; "$x$y"/e;' foo.zsync | tee foo.tr.zsync | cksum | sed -e 's/[ 	][0-9].*//'`
+-[ $x = 4103379992 ]
++[ $x = 3456223344 ]
+ rm foo.zsync
+ 
diff --git a/zsync.spec b/zsync.spec
index 93d256d..1bb1f8c 100644
--- a/zsync.spec
+++ b/zsync.spec
@@ -5,10 +5,11 @@ License:       Artistic-2.0 and Zlib and NTP and LicenseRef-Fedora-Public-Domain
                # Zlib: zlib/*
                # NTP: base64.c
                # PD: librcksum/*
-Version:       0.6.5
+Version:       0.6.3
 Release:       %autorelease
 
 Source0:       https://zsync.moria.org.uk/download/%{name}-%{version}.tar.bz2
+Patch0:        zsync-0.6.3-fix-tests.patch
 
 BuildRequires: gcc
 BuildRequires: make